Original North American area codes (original) (raw)

The original North American area codes were established by the American Telephone & Telegraph Company (AT&T) in the years immediately following World War II. Creating a comprehensive and universal, continent-wide telephone numbering plan was a basic requirement for nationwide Operator Toll Dialing which had the goal of speeding the connecting times for long-distance calling by eliminating intermediary telephone operators. It had the eventual benefit of direct distance dialing (DDD) by telephone subscribers. It established a uniform destination addressing and call routing system for all telephone networks in North America that had become an essential public service.